Question:medium
If the coefficient of \(x^4\) in the binomial expansion of \((4x + a)^7\) is -1120, then the value of \(a\) is equal to
If the coefficient of \(x^4\) in the binomial expansion of \((4x + a)^7\) is -1120, then the value of \(a\) is equal to
Show Hint
Always ensure the exponent of the variable matches the requested power before solving for the unknown constant. Here, \(a^3 = -1/8\) directly implies \(a\) must be negative.
Updated On: Jun 24, 2026
- \(\frac{1}{2}\)
- \(\frac{1}{4}\)
- \(\frac{-1}{2}\)
- \(\frac{1}{8}\)
- \(\frac{-1}{8}\)
Show Solution
The Correct Option is C
Solution and Explanation
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